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Finding the Fourth Proportional to 20.20, 28 and 19.28

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Solution

The fourth proportional to 20.20, 28 and 19.28 is: 26.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.20 : 28 = 19.28 : x
  2. Step 2: Convert to fraction form
    20.20/28 = 19.28/x
  3. Step 3: Cross multiply
    20.20x = 28 × 19.28
  4. Step 4: Simplify right side
    20.20x = 539.84
  5. Step 5: Solve for x
    x = 539.84/20.20
  6. Step 6: Final answer
    x = 26.72

Related Problems

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Double scale
Find fourth proportional to 21.20, 29.39 and 20.28
Similar ratio
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.